Senior Java Integration Developer

Senior Java Integration Developer Sydney | 100% Onsite | 6 Month Contract | Must Hold Active Baseline Clearance or Higher An exciting opportunity is available for a highly experienced Senior Java Integration Developer to lead the design and delivery of mission critical integration services within a secure government-focused environment. This is a hands-on technical leadership role where you will be responsible for designing, developing and supporting a complex integration layer that connects large-scale digital platforms with government backend systems. You will work on high-volume, highly secure services handling sensitive data and will play a key role throughout development, testing, deployment and production support. Due to the nature of the environment, this position is fully onsite in Sydney and requires an active Australian Government Baseline Clearance or higher (NV1/NV2). The Opportunity As the technical authority for the integration platform, you will lead the design and development of secure Java-based integration services that facilitate the transformation and exchange of data between enterprise applications and government systems. You will work closely with architects, delivery teams, government stakeholders and testing teams to ensure solutions are secure, scalable, resilient and compliant with government standards. Key Responsibilities Lead the technical design of enterprise integration solutionsDevelop and maintain Java-based integration microservicesDesign and implement JSON to SOAP/XML transformationsBuild asynchronous processing capabilities including queuing, retries and failure managementDeliver secure integrations using mutual TLS, PKI and digital message signingDefine and maintain interface contracts and schema mappingsBuild test harnesses and integration stubs to accelerate deliverySupport integration, performance and security testing activitiesTroubleshoot complex issues within secure environmentsAssist with deployment planning, cutover activities, go-live support and hypercareMentor developers and provide technical leadership across integration initiativesCollaborate with architecture, DevOps, testing and business stakeholders Technical Environment Technologies Java (Current LTS)Spring BootSpring Integration or similar frameworks Integration SOAP/XMLWSDLXSDJAXBREST/JSONMessage Queuing Security Mutual TLS (mTLS)PKI and Certificate ManagementTLS 1.2+OAuthDigital SignaturesIP Allow Listing Platform & Infrastructure KubernetesAPI GatewaysIngress ControllersLoad BalancersContainerised EnvironmentsCI/CD Pipelines Data & Monitoring PostgreSQL / MariaDB or similarStructured Audit LoggingSIEM IntegrationApplication Performance Monitoring (APM) Essential Skills & Experience To be successful in this role, you will demonstrate: Active Australian Government Baseline Clearance or higher (NV1/NV2)Availability to commence immediately and no later than 1 November 202612+ years of commercial Java development experienceExtensive experience delivering enterprise integration solutions at senior or lead levelStrong expertise designing and building SOAP/XML web servicesProven experience with WSDL, XSD, schema transformations and JAXBHands-on delivery of certificate-based authentication, mTLS and message signingExperience building high-volume, resilient integration platformsStrong knowledge of asynchronous processing, queuing and error handling patternsKubernetes and containerised microservices expertiseExcellent troubleshooting and diagnostic skills across application, infrastructure and networking layersStrong stakeholder engagement and communication skills Highly Desirable Experience integrating with Australian Government agenciesKnowledge of PSPF, ISM and IRAP frameworksExperience within travel, aviation or passenger data environmentsLarge-scale public sector digital service delivery experiencePerformance testing and optimisation of enterprise integration services What We're Looking For You are a senior engineer who enjoys owning solutions from design through to production. You are comfortable operating as the technical lead, making critical decisions and guiding teams through complex delivery challenges. You bring a pragmatic approach to problem-solving, work effectively under pressure and have a strong focus on security, quality and operational excellence. Important Requirements Must hold a current Australian Government Baseline Clearance or higherMust be able to work onsite in Sydney five days per weekRemote access to the secure environment is not availableMust be available to commence immediately, and no later than 1 November 2026Occasional out-of-hours support may be required during releases, cutovers and hypercare periods Apply Now If you are an experienced Senior Java Integration Developer with deep expertise in secure enterprise integrations and an active security clearance, we'd love to hear from you. Join a high-performing team delivering nationally significant digital services within a secure and complex environment. Linda Jona Consultant Let's connect ManpowerGroup is committed to being a Diversity Confident Recruiter and encourages applications from people from a diverse range of backgrounds, including people with a disability. Please indicate your preferred method of communication in your resume and please let us know if you require any reasonable adjustments should you be contacted for an interview. Aboriginal and Torres Strait Islander people are encouraged to apply. By submitting your resume and other personal information with this application you are consenting to this information being collected in line with our privacy policy. Follow the link to learn more - www.manpowergroup.com.au/privacy-policy State: QLD, licensee/s Manpower Services (Australia) Pty Ltd, LHL-02026-D5L4Q. State: QLD, LHL-02014-Y5F6D. State: SA, licensee/s Manpower Services (Australia) Pty Ltd, LHS 288856